#include <bits/stdc++.h>
using namespace std;

#define int int64_t
#define endl "\n"

using PII = pair<int, int>;
using TII = tuple<int, int, int>;
template<class T>
using V = vector<T>;
using i64 = long long;
using i128 = __int128;
using u64 = unsigned long long;

#define FOR(i, a, b) for (int i = (int)(a); i <= (int)(b); i++)
#define FOR2(i, a, b, c) for (int i = (int)(a); i <= (int)(b); i += c)
#define FORD(i, b, a) for (int i = (int)(a); i >= (int)(b); i--)
#define FORD2(i, b, a, c) for (int i = (int)(a); i >= (int)(b); i -= c)
#define ALL(a) a.begin(), a.end()
#define RALL(a) a.rbegin(), a.rend()
#define lowbit(x) ((x)&(-x))
#define RE return;
#define Yes cout << "Yes" << endl;
#define YES cout << "YES" << endl;
#define No cout << "No" << endl;
#define NO cout << "NO" << endl;
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define sz size()

void solve () {
    int n;
    cin >> n;
    V<int>w (n);

    for (auto& x : w)cin >> x;

    map<int, int>mp;
    V<int>sql;
    for (auto x : w)mp[x]++;

    for (auto [x, y] : mp)sql.eb (x);

    int ans = 0;

    sort (ALL (w));

    FOR (i, 0, 100){
        int cnt = 0;
        FOR (l, 0, sql.sz - 1){
            FOR (r, l, sql.sz - 1){
                if (l == r && 2 * sql[l] == i){
                    cnt += mp[sql[l]] / 2;
                } else{
                    if (sql[l] + sql[r] == i){
                        cnt += min (mp[sql[l]], mp[sql[r]]);
                    }
                }
            }
        }
        ans = max (ans, cnt);
    }
    cout << ans << endl;
}

signed main () {
    int Task = 1;

    ios::sync_with_stdio (false);
    cin.tie (nullptr);
    cin >> Task;

    while (Task--) {
        solve ();
    }

    return 0;
}